Heat-assisted magnetic recording (HAMR) is a technology which allows large increases in information storage density compared to conventional hard disk drives. A laser is used to momentarily heat the recording area of the medium to reduce its coercivity below that of the applied magnetic field from the recording head. The heated region is then rapidly cooled in the presence of the applied head field whose orientation encodes the recorded data. Due to the use of heat during the recording process, lubricants used with HAMR systems must be thermally stable.
HAMR requires the heating of magnetic media to or above the Curie temperature (TC), which may exceed 700° K. Lubricant molecules used on the disk interface are thus exposed to high temperatures that may cause them to degrade, causing problems for head operation and recording performance. Lubricant molecules are also exposed to high shear stress conditions during disk operation.
Conventional perfluoropolyether (PFPE) lubricants used to coat current magnetic recording media surfaces, such as Z-Dol, Z-Tetraol, DEPH, and Fomblin, may not withstand the recording temperatures used in HAMR systems. There is therefore a need for improved lubricants able to withstand high temperature and shear stress conditions.